engine malfunction failure and BMW wants to reinstall the car's software in order to debug the issue. apparently they can't reinstall the software, because the factory amp does not exist - it's been replaced with a mobridge pre-amp, helix p-dsp, alpine amps et al.

they also claim to be unable to bypass the missing amp in order to complete the software install.

Its known that if the head unit is missing
that this is true. There computer/repair is to dumb to ignore the lack of the original configuration .
If the amp is a L7 I can kind of see how that might be possible, since there is more communication than just audio.
By the way what is the issue?
The coding board setup can bypass some of this stuff as its
more basic in the way it works, but the dealership won't use
that.
if you still have it maybe you could plug the L7 back in temporarily.
You probably wouldn't have to hook it back up to the speakers.
Possible solution have them program the radio to Hi Fi
remove the L7 from the Most loop then program, just a guess.

Its known that if the head unit is missing.
That this is true, there computer is to dumb to ignore the lack of the original
configuration .
If the amp is a L7 I can kind of see how that might be possible, since there is more communication than just audio.
By the way what is the issue?
The coding board setup can bypass some of this stuff as its
more basic in the way it works.
if you still have it maybe you could plug the L7 back in temporarily.

the factory head unit remains intact, was not touched and is operational. the original system was "individual audio".

I'm not sure what the engine malfunction is, BMW was advised to reinstall the software to help debug the problem.

although I still have the factory amp, the connections for it do not seem to exist anymore (musicarnw system, they also did the physical installation). emailed ken about this yesterday as well. guessing it'll have to get reconnected one way or another, so the software update can be done. haven't seen this sort of thing mentioned anywhere previously.

I don't think VP would cut wires he always does a reversible installation.
Also he will know what to do.
That preamp hasn't been out very long,at least in the analog configuraton . I would also talk to mobridge about this.

There should not be any connector cut, otherwise the DA2 would not have been working at all. It requires the MOST connector as is. In the worst case it may be missing a MOST jacket which you can get at the dealer.

There should not be any connector cut, otherwise the DA2 would not have been working at all. It requires the MOST connector as is. In the worst case it may be missing a MOST jacket which you can get at the dealer.

Unplug DA2 and connect OEM amp back. The dealer is correct.

that was actually my first response to them, but I didn't have the factory amp with me at the time and they didn't have a spare one. when I got home and looked at the factory amp, the connection is entirely different whereas the da2 is just taking the optical in.

sounds like the "MOST jacket" takes the optical and converts it for the factory amp? do you know the part number? I don't have this cable/adapter, perhaps ken held onto it. what about power for the amp?

There should not be any connector cut, otherwise the DA2 would not have been working at all. It requires the MOST connector as is. In the worst case it may be missing a MOST jacket which you can get at the dealer.

Unplug DA2 and connect OEM amp back. The dealer is correct.

just to make sure we're talking about the same type of amp. here is a picture of the connections I am referring to vs the more typical optical cable running into the da2.

that was actually my first response to them, but I didn't have the factory amp with me at the time and they didn't have a spare one. when I got home and looked at the factory amp, the connection is entirely different whereas the da2 is just taking the optical in.

sounds like the "MOST jacket" takes the optical and converts it for the factory amp? do you know the part number? I don't have this cable/adapter, perhaps ken held onto it. what about power for the amp?

12V and ground are at the 20-pin harness. The MOST jacket looks to be missing.

12V and ground are at the 20-pin harness. The MOST jacket looks to be missing.

gotcha. not really sure what the MOST jacket looks like, can't find anything online with that search term (pointers?), but I also haven't seen the 20-pin connection in my car. I am guessing it's there, just behind or hidden from view. still waiting for ken to reply, hopefully it's less problematic then it seems.

gotcha. not really sure what the MOST jacket looks like, can't find anything online with that search term (pointers?), but I also haven't seen the 20-pin connection in my car. I am guessing it's there, just behind or hidden from view. still waiting for ken to reply, hopefully it's less problematic then it seems.

The 20-pin is the OEM speaker main connector harness -your aftermarket amps outputs are wired to it. You need to remove the left trunk trim completely to see the whole OEM wiring.

just to make sure we're talking about the same type of amp. here is a picture of the connections I am referring to vs the more typical optical cable running into the da2.

The "MOST jacket" that Technic is referring to is there. It's the housing plugged in to the MOST connector on the amp in the picture. It's kind of a mating adaptor, but the inner 2-pin housing is the same. You'll need to remove the 2-pin FO connector from the Mobridge "MOST Jacket" and insert it into that housing before it will plug in to the amp.

The 20 pin connector to provide power to the amp is still intact in the car. Here's a pic of your amp rack:

The L7 20 pin connector is in down in the cavity forward (towards the wheel well) of the DA2. Just unplug that from the Technic connector, plug it in to the L7 amp, plug the MOST connector in to the L7 amp and you should be good to go.

The "MOST jacket" that Technic is referring to is there. It's the housing plugged in to the MOST connector on the amp in the picture. It's kind of a mating adaptor, but the inner 2-pin housing is the same. You'll need to remove the 2-pin FO connector from the Mobridge "MOST Jacket" and insert it into that housing before it will plug in to the amp.

The 20 pin connector to provide power to the amp is still intact in the car. Here's a pic of your amp rack:

[ removed link ]

The L7 20 pin connector is in down in the cavity forward (towards the wheel well) of the DA2. Just unplug that from the Technic connector, plug it in to the L7 amp, plug the MOST connector in to the L7 amp and you should be good to go.

thanks Tom!

ah yes, I see now that the MOST jacket is there and I can remove it from the L7 amp (didn't realize that is what was referred to as the jacket). also found a MOST network cable in the box of manuals you gave me and think I see how it comes together or at least it's making a bit more sense now. will see what I can do when I get back to the shop with the L7 amp.

Yes, you will need to re-install the factory amp in order to update your software. It's the same reason why when many people install aftermarket decks, they install the stock unit in the trunk so the dealer can run diagnostics and update the software.

had to remove the left trunk liner and pull the amp rack out, to gain access to the 20 pin power harness. wasn't that hard, but the tech did mention they apparently make a 20 pin y-splitter that could be used to avoid having to take the amp rack out. haven't seen it myself, but that could be worth while.

Yes but if you jumper the optical connectione most ring is intact ,but I suppose the BMW computer still looks at the VO to run a full diagnostic and repair solution. So if you jumpered the Most Bus and removed it from the VO would it work . If you programmed for Hi Fi and completed the Most Bus it should work anyway should it not?